Structural wall and method



Nov. 26, 1968 s. c. DOUGHTY 3,412,562

STRUCTURAL WALL AND METHOD Filed Nov. 14, 1967 2 Sheets-Sheet 1 F l g. 6INVENTOR.

S. CLIFFORD DOUGHTY Attorneys Nov. 26, 1968 Filed NOV. 14, 1967 54 5o 62I H, L Y

S. C. DOUGHTY STRUCTURAL WALL AND METHOD 2 Sheets-Sheet 2 INVENTOR. S.CLIFFORD DOUGHTY Attorneys United States atent 3,412,562 STRUCTURAL WALLAND METHOD Samuel Clifford Doughty, Burlingame, Califi, assignor to BenC. Gerwick, Inc., San Francisco, Calif a corporation of CaliforniaContinuation-impart of application Ser. No. 418,778,

Dec. 16, 1964. This application Nov. 14, 1967, Ser.

Claims. (Cl. 6139) ABSTRACT OF THE DISCLOSURE A structural wall formedwith a number of upright and laterally spaced apart H-beam memberswherein the span between members is provided relative to the thicknessof the wall so as to provide arch action support to the wall when earthon one side of the wall is excavated. After excavation, a finish facingis applied to the exposed wall carried by means attached to the exposedflanges of the H-beam members or by attachment to the concrete. To formthe wall, the H-beam members are lodged in the ground as guided bypre-drilled holes formed at intervals and followed by the excavation ofmaterial from between the webs of the H-beams. A slurry is maintained inthe trench being formed and concrete is poured employing the tremiemethod.

Cross-reference to related application This application is acontinuation-in-part of US. patent application, Ser. No. 418,778, filedDec. 16, 1964, now abandoned in the name of S. Clifford Doughty.

Background of the invention This invention relates to concrete wallcontsructions and to a method of constructing same.

In the construction of large buildings, subways, and other structures incities, a major problem is the provision of a supporting structure,installed before or during excavation, which will hold back thesurrounding ground and provide lateral support to adjacent buildings,streets, etc. In the past this has often been accomplished by theinstallation of steel sheet piles driven before excavation starts, or bythe use of soldier beams and lagging. The latter method has thedisadvantage that it drains the surrounding soil, frequently permittingthe adjoining buildings to settle. Installation of steel sheet piles isexpensive and usually causes considerable vibration and noise.

Another approach has been the construction, before excavation starts, ofa concrete wall. This concrete wall can usually be installed with aminimum of noise and vibration and can serve as a part of the permanentwall of the structure. Spaced holes are drilled, then filled withconcrete. Later, additional holes are drilled between and filled withconcrete. During the hole drilling, a slurry, such as a bentoniteslurry, keeps the hole from caving.

Still another method contemplates excavation of a trench in successivesections with a clamshell bucket while the trench is kept filled with abentonite slurry. The sections are then filled with concrete placed bythe tremie method. A reinforcing steel cage is placed in the bentoniteslurry before the concrete is poured to provide structural strengthlater. This latter method is very expensive. The joints between adjacentsections often weep or leak. Further, in very unstable soils, thesection of trench that can be excavated at any one time must be kept toa minimum, which therefore begins to approximate the older drilled-holetechnique referred to initially above. The only support to the sides ofthe trench is from the bentonite slurry and is not entirelysatisfactory. Further, this method requires much time.

Objects and summary of the invention In general, it is an object of thisinvention to overcome these and other shortcomings of earlier Schemesand to provide an improved wall construction technique havingsignificant additional advantages, as well.

It is another object of the invention to provide an improved method ofconstructing a structural wall which is to be subjected to earthpressures acting laterally against it.

It is a further object to provide an improved wall structure accordingto the invention herein; excavation and also serves thereafter as thestructural wall of the construction being erected.

Another object is the provision of an improved wall structure and methodfor excavations in sandy or other uncertain strata.

These and other objects of the invention will be more clearly understoodfrom the following detailed description of preferred embodiments of themethod and wall construction herein.

FIGURES 1 through 5 diagrammatically illustrate in plan view steps of amethod of constructing a wall structure according to the inventionherein;

FIGURE 6 is a diagrammatic plan view of a wall structure according tothe invention herein,

FIGURE 6a schematically representing tremie placement of concrete;

FIGURE 7 is a section view in plan showing a wall construction wherein afinish facing has been attached to concrete portions of the wall; and

FIGURES 8 and 9 are diagrammatic perspective views showing a sequence ofsteps followed according to another embodiment of the method of theinvention.

In general, to construct an improved wall structure according to theinvention, a method is provided which, in general, follows the steps ofdrilling a series of upright holes into the earth. The holes are spaceda predetermined distance apart. An elongate structural member, such as asoldier beam, is next guided into each hole. The next step includes theforming of a trench between the inserted soldier beams whereby thesoldier beams serve as trench braces to provide support to opposed wallsof the trench. The trench is then filled with a hardenable cementitiousmaterial such as concrete to form a wall in the trench.

Ordinarily after permitting the material to harden, earth will beremoved from one side of the wall which has the effect of subjecting thewall to earth pressures acting against the unexcavated side of the wall.The thickness of the trench with respect to the span of the wall betweeneach adjacent pair of structural members is sufficiently thick totransmit by arch action the load of earth pressure acting against oneside of the wall after the earth is removed from the other side of thewall.

In weak or caving soil a slurry is maintained in the holes so as to sealthe exposed surfaces therein. Also, in one preferred form of the method,the hole diameter is such that the beam fits snugly into the hole tosupport the sides of the hole during excavation between beams.

Description of preferred embodiments One preferred method ofconstructing the wall proceeds as now to be described with particularreference to FIG- URES l-6 of the drawings.

Initially, the first step includes drilling a series of holes 10 ofpredetermined diameter, D. The axis of the holes as shown herein isvertically into the earth, and the axes are spaced apart at intervalswhich, as will be later seen below, define the span, S, of verticalslabs of concrete. A volume of slurry, such as a drillers mud, ismaintained in each hole to seal the exposed surfaces therein and providelateral support to the walls of each hole. A slurry of bentonite ispreferable for this purpose. The next step includes inserting astructural steel H-beam member 12 into the slurry in each hole. Beammembers each include spaced apart parallel flange portions 14, 16 andweb portions 18 extending normal to the flange portions along the lengththereof.

The flanges of adjacent beam members are aligned in spaced planes 20, 22to generally define the wall thickness to be formed. The diameter of theholes is comparable to the width of the web portion 18 as shown in FIG-URE 3. The next step includes excavating between the planes 20, 22 andbetween the web portions 18 of each adjacent pair of beam members 12 soas to form an elongated trench 24 having opposing sidewalls 26, 28.Sidewalls 26, 28 are braced at intervals by the beam members 12. Duringthe foregoing excavating step, suflicient slurry is maintained in trench24 to seal the exposed surfaces thereof and to give lateral support toprevent cave-in.

The next step is to fill the trench sections, preferably successivelybetween each adjacent pair of beam members 12 with a cementitiousmaterial such as concrete using a tremie pipe 29 so as to displace theslurry therein. Subsequently, the cementitious material is permitted toharden so as to form a wall.

As is known in the art, a tremie pipe for the pouring of a wet concretemix consists of a straight metal pipe or conduit open at both its upperand lower ends, and communicating at its upper end with a hopper intowhich the wet mix is introduced. At the beginning of the pour the lowerend of the pipe is positioned near the bottom of the space to be filled,and as the level of the poured concrete rises about the lower end of thepipe, the pipe is gradually elevated while introduction of concretecontinues without interruption.

As is known, concrete may be placed under water through a tremie orwatertight pipe 12 in. to 24- in. in diameter, having a conical shapedtop the better to receive the charge of concrete. At the start ofoperations the mouth of the pipe is set on the bottom and the pipefilled with concrete. The pipe is then slowly raised, allowing theconcrete to flow out as more concrete is poured in at the top, alwayskeeping the pipe fully charged. It is essential, once the concretingoperations are started, that the lower end of the pipe be kept buried inthe concrete until the entire operation is completed. In this manner,washing out of the cement is prevented. The upper layer of concretedisplaces the Water, and laitance is kept at the surface of the concretewhence it may be finally and effectively removed. If at any time duringthe operations the bottom of the pipe loses contact with the concrete,the charge will be lost; therefore particular care must be taken incontinuing operations not to stir up the fresh concrete in place. Tremieoperations should be continuous until the structural unit has beencompleted.

Tremie concrete must be of a consistency that will ermit it to flowreadily and it therefore requires more cement and water than concreteplaced in the dry. A conventional slurry of the above type consistsmainly of water.

While clamshell or other types of excavators may be used to form thetrench portions defined between beams, it is particularly preferred toaccomplish the excavation between beam-filled holes 10 by drilling holes30 intermediate holes 10. For purposes which will become furtherapparent below it is prefer-red to form holes 10 and 39 with a diameter,D, whereby the thickness of trench 24, as defined between planes 26, 28,is proportionate to the span, S, of each vertical slab 32 of concrete soas to transmit by arch action (as suggested by lines 34 in FIGURE thelaterally acting load of earth which bears against the unexcavated sideof the wall.

Thus, each slab 32 includes a portion 33 of concrete active in providingthe above mentioned arch action support, and other portions 35 which areinactive as sometimes referred to a dead concrete. Each slab 32 ofconcrete is positively locked by flanges 14, 16.

In one particularly preferred construction, the diameter, D, isproportional to the span, S, in a relationship of 1 to 2. Thus, wherediameter D is two feet the distance between centers of holes 10 ispreferably four feet. The diameter D of holes 30, being comparable tothe diameter of holes 10, therefore serves to define wedges of earth 36which are removed by suitable excavating equipment.

With reference to FIGURE 6, a wall construction formed by the foregoingtechnique is shown and it will be readily apparent that after the earthis excavated away from one side of the wall sufliciently to exposeflange portions 16, attachment means can be welded to the flanges 16 soas to project therefrom and aid in the placing of an inner finish facing40 of concrete. This may, for example, be about six inches in thickness.Thus, after excavating away from one side of the structural wall, theside of the wall will be thoroughly cleaned off and attachment meanssuch as stud anchors 42 can then be welded to the exposed flanges 16.Stud anchors 42 are bent over atthe end and serve to engage rods 44 of areinforcing steel matrix 46. After erecting a form to define the innerwall surface 48, the finished wall can be poured.

As shown in FIGURE 7, stud anchors can also be embedded into theconcrete portions 35.

From the foregoing, it will be apparent that there is provided a wallconstruction for imparting lateral support to earth adjacent one sidethereof. The wall comprises a series of elongated structural pre-formedbeam members such as the H members which are disposed upright in a line.Beam members include spaced parallel sides aligned in spaced parallelplanes wherein the planes serve generally to define the thickness of thewall. A vertical slab of poured concrete is formed between the planesand spans the distance between each adjacent pair of beam members so asto engage webs of the beam members. Each slab is sufficiently thick withrespect to the span thereof to transmit by arch action to its associatedpair of beam members the load of earth pressure acting against theunexcavated side of the wall. Thus, the trench is securely braced atclose intervals.

The wall construction forms not only the wall of the structure but atthe same time provides a soil support bulkhead also useful duringexcavation and thereby eliminates considerable duplication ofconstruction expense which conventionally is encountered. The wallconstruction further provides weldable regions conveniently located soas to provide the attachment means for supporting the finishing facing40, or in the alternative, wide, accessible zones of concrete where itis preferred to anchor to concrete.

From the foregoing, it will be further evident that the method permitsthe construction of a soil support bulkhead and a structural wall inuncertain strata by taking advantage not only of the drilling mud butalso by utilizing the soldier beams as trench braces during theformation of the wall. These same soldier beams serve to provide abending support against the earth pressures after the wall is completedand the earth excavated away from one side.

From the foregoing benefits and advantages it will be readily evidentthat this invention overcomes the difficulties outlined initially aboveand results in a permanent wall which offers considerable economy inconstruction. The wall can be constructed much more rapidly and providesa positive trench bracing support during the period of construction. Thewall provides further a positive joint between adjacent adjoiningsections of the wall and facilitates forming and pouring of an insidefacing or finish wall. As also noted above, the wall constructionderives vertical bending strength from the soldier beams rather thanbeing dependent on the concrete. Finally, the wall as formed by theabove method provides a relatively uniform thickness of wall, which inmany cases will permit better clearance and closer approaches toadjoining buildings and structures.

Where ground conditions dictate, it may be desirable or necessary toform the series of drilled holes of a considerably reduced diameter asshown by the holes 50 in FIGURE 8. Thus, the series of holes 50 arealigned along the line 52 adapted to define the central plane of a wallto be formed.

Each of holes 50 serves to guide an elongated H-beam member 54 along theaxis of the hole 50 so as to properly maintain the H-beam member 54 inits proper disposition. Thus, the bottom end of H-beam member 54 isprovided with an elongated projecting guide element in the form of thecylindrical element 56 formed with a conicallypointed end 58. Element 56is attached to the lower end of member 54, as by welding.

Accordingly, after drilling a series of upstanding holes 50, H-beammembers 54 are formed with a guide element 56 which will cooperate in aguiding relation with respect to holes 50. Subsequently, H-beam members54 are driven into the earth, guided by elements 56.

In FIGURE 9, the application of a driving force to H-beam member 54 isindicated by the arrow 62. After having lodged members 54 in the earthwith the flanges thereof aligned in spaced parallel planes, excavationbetween the webs of members 54 proceeds as above described with respectto the procedure represented in FIG- URES 16.

By restricting the size of holes 50 to the generally reduced diameter ofthe guiding element 56, it has been found that in many instances, it isunnecessary to maintain a slurry Within the drilled holes inasmuch asthe smaller diameter hole is less subject to caving.

Thus, it will be readily evident that the relatively easily accomplishedaccuracy of locating the drilled guide holes 50 or the larger diameterholes 10 may be first accomplished and then utilized to properly guidethe H-beam members into accurate alignment with respect to other memberswhich will form portions of the wall structure. Where beam drivingtechniques have been developed to accomplish comparable accuracy, itmay, under certain soil conditions, be desirable to merely drive thebeams directly into the earth without prior drilling of a guiding holefor receiving the beam.

While there has been shown and described and pointed out the fundamentalnovel features of the invention as applied to a preferred embodiment, itwill be understood that various omissions and substitutions and changesin form and details of the embodiment illustrated may be made by thoseskilled in the art, without departing from the spirit of the invention.For example, some of the foregoing advantages may be attainableutilizing soldier beams such as pipe piles, or pre-stressed orpro-formed concrete beams rather than the H-shaped structural members ofthe preferred embodiment above.

Therefore, it is the intention to be limited only by the scope of thefollowing claims.

I claim:

1. In a method of constructing a wall structure those steps comprisingdrilling a plurality of at least two upstanding holes of predetermineddiameter into the earth spaced a predtermined distance apart, insertingan elongate structural member into each hole, the dimension of eachmember in a direction normal to a plane between said holes beingcomparable to the diameter of said holes to apply support to oppositesides of said holes, forming a substantially rectilinear trench betweensaid inserted members whereby said members serve as trench braces toprovide support to opposed walls of the trench, and filling the trenchbetween said braces with hardenable cementitious material to form a wallin said trench, permitting the material to harden, and removing earthfrom one side of the wall after the material hardens, the thickness ofsaid trench with respect to the span of Wall between said structuralmembers being sufiiciently thick to transmit by arch action the load ofearth pressure acting against one side of the wall after the earth isremoved from the other side of the wall.

2. The method of constructing a structural wall comprising the steps ofdrilling a series of holes of predetermined diameter generallyvertically into the earth at spaced apart intervals, maintaining avolume of slurry in each hole to seal the exposed surfaces therein,inserting a structural steel H beam member having web and spaced flangeportions into each hole, the flanges of adjacent beam members beingaligned in spaced planes to generally define the wall thickness, thediameter of said holes being comparable to the Width of the web of thebeam member therein, excavating between said planes and the web portionsof each adjacent pair of beam members to form an elongated trench havingopposing side walls braced at intervals by said beam members,maintaining sufficient slurry in the trench to seal the exposed surfacesthereof, filling the trench portions between each adjacent pair of beammembers with cementitious material using a tremie pipe so as to displacethe slurry therein, and permitting the cementitious material to hardento form a wall.

3. The method of constructing a structural wall comprising the steps ofdrilling a series of holes of predetermined diameter generallyvertically into the earth at spaced apart intervals, maintaining avolume of slurry in each hole to seal the exposed surfaces therein,inserting a structural steel H beam member having web and spaced flangeportions into each hole, the flanges of adjacent beam members beingaligned in spaced planes to generally define the wall thickness,excavating between said planes and the web portions of each adjacentpair of beam members to form an elongated trench having opposing sidewalls braced at intervals by beam members, maintaining sufficient slurryin the trench to seal the exposed surfaces thereof, filling the trenchportions between adjacent pairs of beam members with cementitiousmaterial using a tremie pipe so as to displace the slurry therein, andpermitting the cementitious material to harden to form a wall, followedby the further steps of excavating the earth away from one side of thewall to expose said flange portions, and leaving the other side of thewall to remain under lateral earth pressure acting thereagainst.

4. The method of constructing a structural wall comprising the steps ofdrilling a series of holes of predetermined diameter generallyvertically into the earth at spaced apart intervals, maintaining avolume of slurry in each hole to seal the exposed surfaces therein,inserting a structural steel H beam member having web and spaced flangeportions into each hole, the flanges of adjacent beam members beingaligned in spaced planes to generally define the wall thickness, thediameter of said holes being comparable to the width of the web of thebeam member therein, excavating between said planes and the web portionsof each adjacent pair of beam members to form an elongated trench havingopposing side walls braced at intervals by said beam members,maintaining sufficient slurry in the trench to seal the exposed surfacesthereof, filling the trench portions between each adjacent pair of beammembers with cementitious material using a tremie pipe so as to displacethe slurry therein, and permitting the cementitious material to hardento form a wall, wherein said excavating step is performed by drillinggenerally vertical holes into the earth between each adjacent pair ofthe first named holes, and thereafter removing any remaining unexcavatedearth lying between said planes.

5. In a method of constructing a wall structure, the steps comprising:drilling upstanding spaced apart holes in the earth, inserting H-beammembers into the holes, said members including a web portion extendinglongitudinally therealong and spaced parallel flanges, the flanges beingsnugly received in said holes and lying in spaced parallel planes tosubstantially define the thickness of the wall structure, excavatingearth from between said members to form a trench, filling the trenchdefined between two adjacent H-beam members in said trench with ahardenable cementitious material to form a Wall portion in said trench,the spacing between said two adjacent H-beam members being related tothe wall thickness to define the span and thickness of the Wall portiontherebetween sufficient to provide arch action support to the load ofearth pressure acting against one side of the wall portion when earth onthe other side has been removed, permitting the cementitious material toharden, and removing earth from one side of the wall after the materialhardens,

6. In a method of constructing a wall structure, the steps comprising:drilling upstanding spaced apart holes in the earth, guiding H-beammembers into the holes, said members including a web extendinglongitudinally therealong between spaced parallel flanges, the flangeslying in spaced parallel planes to substantially define the thickness ofthe wall structure, excavating earth from between said members to form atrench, filling the trench defined between two adjacent H-beam membersin said trench with a hardenable cementitious material to form a wallportion in said trench, the spacing between said two adjacent H-beammembers being related to the wall thickness to define the span andthickness of the wall portion therebetween sufficient to provide archaction support to the load of earth pressure acting against one side ofthe wall portion when earth on the other side has been removed,permitting the cementitious material to harden, and removing earth fromone side of the wall after the material hardens.

7. In a method of constructing a wall structure, the steps comprising:lodging upstanding spaced apart H- beam members in the earth, saidmembers including a web portion extending longitudinally therealong andspaced parallel flanges, the flanges lying in spaced parallel planes tosubstantially define the thickness of the wall structure, excavatingearth from between said members to form a trench, filling the trenchdefined between two adjacent H-beam members in said trench with ahardenable cementitious material to form a wall portion in said trench,the spacing between said two adjacent H-bearn members being related tothe wall thickness to define the span and thickness of the wall portiontherebetween sufficient to provide arch action support to the load ofearth pressure acting against one side of the wall portion when earth onthe other side has been removed, permitting the cementitious material toharden, and removing earth from one side of the wall after the materialhardens.

8. In a method of constructing a wall structure, the steps comprising:drilling upstanding spaced apart guide holes in the earth, formingH-beam members at one end thereof with an elongated projecting guideelement adapted to cooperate in guiding relation with said holes,inserting said guide elements of said H-beam members into the holes anddriving said H-beam members into the earth guided by said elements, saidH-beam members ineluding a web portion extending longitudinallytherealong and spaced parallel flanges, said flanges lying in spacedparallel planes to substantially define the thickness of the wallstructure, excavating earth from between said members to form a trench,filling the trench defined between two adjacent H-beam members in saidtrench with a hardenable cementitious material to form a Wall portion insaid trench, the spacing between said two adjacent H-beam members beingrelated to the wall thickness to define the span and thickness of thewall portion therebetween suflicient to provide arch action support tothe load of earth pressure acting against one side of the wall por tionwhen earth on the other side has been removed, permitting thecementitious material to harden, and removing earth from one side of thewall after the material hardens.

9. A wall construction for providing lateral support to unexcavatedearth bearing against one side thereof where earth has been excavatedaway from the other side thereof, said wall comprising a series ofstructural steel H-beam members disposed upright in a line and formedwith spaced parallel flange portions lying in spaced parallel planes,said H-beam members further including a web portion disposed normal tothe flange portions, the spacing between said planes substantiallydefining the thickness of the wall, an upstanding slab of tremie-pouredconcrete formed between said planes and spanning the distance betweeneach adjacent pair of said webs to engage said beam members, the frontand back surfaces of said slab lying substantially in said planes, eachslab being sufficiently thick with respect to the span thereof totransmit by arch action, defined between said planes, to the webs of itsassociated pair of beam members the load of earth pressure actingagainst the unexcavated side of the wall, the wall on the excavated sidethereof being exposed, attachment means projecting from the exposed sideof the wall, and an inner finish facing forming a finished wall surfaceon the excavated side of the wall, said attachment means being embeddedin said facing to support said inner finish facing.

10. A wall construction according to claim 9 wherein the exposed side ofthe wall includes exposed flange portions of said H-beam members, andsaid attachment means projects from said exposed flange portions tosupport said inner finish facing therefrom.

References Cited UNITED STATES PATENTS 592,738 10/1897 Judson 61-392,791,886 5/1957 Veder 6135 3,184,893 5/1965 Booth 52l69 X 3,216,16311/1965 Carew 52-169 X FOREIGN PATENTS 1,127,500 8/1956 France.

OTHER REFERENCES Roads and Streets (publication), November 1962, pp. 21,22 and 23.

JACOB SHAPIRO, Primary Examiner.

Disclaimer 3,412,562.Smuel Clifford Doughty, Burlingame, Calif.STRUCTURAL WALL AND METHOD. Patent dated Nov. 26, 1965. Disclaimer filedJan. 23, 1980, by the assignee, Santa Fe-Pomeroy, Inc. Hereby entersthis disclaimer to claims 9 and 10 of said patent.

[Ojficz'al Gazette, May 6, 1.980.]

